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Title: Intracellular localization of varicella-zoster virus ORF39 protein and its functional relationship to glycoprotein K

Abstract

Varicella-zoster virus (VZV) encodes two multiply inserted membrane proteins, open reading frame (ORF) 39 protein (ORF39p) and glycoprotein K (gK). The HSV-1 homologs of these proteins are believed to act in conjunction with each other during viral egress and cell-cell fusion, and they directly influence each other's intracellular trafficking. However, ORF39p and VZV gK have received very limited study largely due to difficulties in producing antibodies to these highly hydrophobic proteins. To overcome this obstacle, we introduced epitope tags into both ORF39p and gK and examined their intracellular distributions in transfected and infected cells. Our data demonstrate that both ORF39p and gK accumulate predominately in the ER of cultured cells when expressed in the absence of other VZV proteins or when coexpressed in isolation from other VZV proteins. Therefore, the transport of VZV ORF39p and gK does not exhibit the functional interdependence seen in their HSV-1 homologs. However, during infection, the primary distributions of ORF39p and gK shift from the ER to the Golgi, and they are also found in the plasma membrane indicating that their intracellular trafficking during infection depends on other VZV-encoded proteins. During infection, ORF39p and gK tightly colocalize with VZV envelope glycoproteins B, E and H;more » however, the coexpression of ORF39p or gK with other individual viral glycoproteins is insufficient to alter the transport of either ORF39p or gK.« less

Authors:
 [1];  [1];  [2]
  1. Division of Infectious Diseases and Immunology, Saint Louis University School of Medicine, St. Louis, MO 63110-0250 (United States)
  2. Division of Infectious Diseases and Immunology, Saint Louis University School of Medicine, St. Louis, MO 63110-0250 (United States). E-mail: heinemtc@slu.edu
Publication Date:
OSTI Identifier:
20975214
Resource Type:
Journal Article
Resource Relation:
Journal Name: Virology; Journal Volume: 358; Journal Issue: 2; Other Information: DOI: 10.1016/j.virol.2006.08.055; PII: S0042-6822(06)00578-2; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; ANTIBODIES; CELL MEMBRANES; GLYCOPROTEINS; MEMBRANE PROTEINS; VIRUSES

Citation Formats

Govero, Jennifer, Hall, Susan, and Heineman, Thomas C. Intracellular localization of varicella-zoster virus ORF39 protein and its functional relationship to glycoprotein K. United States: N. p., 2007. Web. doi:10.1016/j.virol.2006.08.055.
Govero, Jennifer, Hall, Susan, & Heineman, Thomas C. Intracellular localization of varicella-zoster virus ORF39 protein and its functional relationship to glycoprotein K. United States. doi:10.1016/j.virol.2006.08.055.
Govero, Jennifer, Hall, Susan, and Heineman, Thomas C. Tue . "Intracellular localization of varicella-zoster virus ORF39 protein and its functional relationship to glycoprotein K". United States. doi:10.1016/j.virol.2006.08.055.
@article{osti_20975214,
title = {Intracellular localization of varicella-zoster virus ORF39 protein and its functional relationship to glycoprotein K},
author = {Govero, Jennifer and Hall, Susan and Heineman, Thomas C.},
abstractNote = {Varicella-zoster virus (VZV) encodes two multiply inserted membrane proteins, open reading frame (ORF) 39 protein (ORF39p) and glycoprotein K (gK). The HSV-1 homologs of these proteins are believed to act in conjunction with each other during viral egress and cell-cell fusion, and they directly influence each other's intracellular trafficking. However, ORF39p and VZV gK have received very limited study largely due to difficulties in producing antibodies to these highly hydrophobic proteins. To overcome this obstacle, we introduced epitope tags into both ORF39p and gK and examined their intracellular distributions in transfected and infected cells. Our data demonstrate that both ORF39p and gK accumulate predominately in the ER of cultured cells when expressed in the absence of other VZV proteins or when coexpressed in isolation from other VZV proteins. Therefore, the transport of VZV ORF39p and gK does not exhibit the functional interdependence seen in their HSV-1 homologs. However, during infection, the primary distributions of ORF39p and gK shift from the ER to the Golgi, and they are also found in the plasma membrane indicating that their intracellular trafficking during infection depends on other VZV-encoded proteins. During infection, ORF39p and gK tightly colocalize with VZV envelope glycoproteins B, E and H; however, the coexpression of ORF39p or gK with other individual viral glycoproteins is insufficient to alter the transport of either ORF39p or gK.},
doi = {10.1016/j.virol.2006.08.055},
journal = {Virology},
number = 2,
volume = 358,
place = {United States},
year = {Tue Feb 20 00:00:00 EST 2007},
month = {Tue Feb 20 00:00:00 EST 2007}
}
  • VZV gK, an essential glycoprotein that is conserved among the alphaherpesviruses, is believed to participate in membrane fusion and cytoplasmic virion morphogenesis based on analogy to its HSV-1 homolog. However, the production of VZV gK-specific antibodies has proven difficult presumably due to its highly hydrophobic nature and, therefore, VZV gK has received limited study. To overcome this obstacle, we inserted a FLAG epitope into gK near its amino terminus and produced VZV recombinants expressing epitope-tagged gK (VZV gK-F). These recombinants grew indistinguishably from native VZV, and FLAG-tagged gK could be readily detected in VZV gK-F-infected cells. FACS analysis established thatmore » gK is transported to the plasma membrane of infected cells, while indirect immunofluorescence demonstrated that gK accumulates predominately in the Golgi. Using VZV gK-F-infected cells we demonstrated that VZV gK, like several other herpesvirus glycoproteins, is efficiently endocytosed from the plasma membrane. However, pulse-labeling experiments revealed that the half-life of gK is considerably shorter than that of other VZV glycoproteins including gB, gE and gH. This finding suggests that gK may be required in lower abundance than other viral glycoproteins during virion morphogenesis or viral entry.« less
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  • A sensitive radioimmunoassay for serum antibody to varicella-zoster virus is described; it uses 125I-labeled staphylococcal protein A and a specially designed immunofiltration apparatus. The assay accurately distinguishes between individuals who are susceptible and those who are immune to infection with varicella-zoster virus. In addition, it can detect passive antibody in recipients of varicella-zoster immune globulin. This radioimmunoassay also detects the heterologous antibody responses that occasionally occur in patients infected with herpes simplex virus, which also have been detected by other antibody assays. The particular advantages of this assay are the use of noninfectious reagents, the speed of execution (less thanmore » 3 hr), the requirement for only small quantities of serum (30 microliters), the objectivity of end-point determination, and the capability of screening large numbers of sera. Consequently, this radioimmunoassay is especially useful for the rapid identification of susceptible individuals, which is essential for the appropriate management of patients and hospital personnel after exposure to varicella.« less
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